Three identical train cars, coupled together, are rolling east at 1.5 m/s . A fourth car traveling east at 4.2 m/s catches up with the three and couples to make a four-car train.what is the speed of the 4 car train ?

Here is my Access to https://amu.apus.eduStudent ID: 5562183Password: Royals1964**Go to Lesson, test&Quizzes and Forum Tabs in Course.Class: Introduction to Chemistry with Lab.Lesson 3Discussion Topic: Problem SolvingInstructions: Your initial post over the material outlined above for Topic should be at least 200 words (these must be words that are typed text within the text box of the Rich Text Editor, thus words on any attached documents will not count towards the total).To make your posts, click on START A NEW CONVERSATION above:State your name and Problem Numbers in the title (Title: Jane Doe, Problems 3.95 and 6.30).In addition to your initial posts to the topics in this Week's Forum, you are required to also reply to at least two classmates' original posts, and each reply must be a minimum of 100 words and include direct questions. Your replies can add additional insight to your classmates’ opinions, suggest other alternative approaches, or anything similar. Be sure to read the follow-up posts to your own posts and reply to everyone who comments on your post.For this topic, you will select two problems from the Chemistry: Atoms First, OpenStax text (in the link there is a book), one problem from each of the following two problem sets:For Problem 1: You MUST select a problem from the end of the chapter "Exercises" from Chapter 3: Problems 95-100; Chapter 4: Problems 23-33; Chapter 6: Problems: 19-29. For Problem 2: You MUST select a problem from the end of the chapter "Exercises" from Chapter 6: Problems 30-51.These problems and their discussions will be included together in one post. After you decide which problems you would like to discuss, start a thread in the Topic Forum. You need not fill in the content—only begin a thread with a subject line that includes your name and the problems you will be discussing. When you are ready to fill in the details of the post, you can simply go back into your post and click “Edit” and put the information into your post. By starting your post, you are claiming your problems and no other student is allowed to choose the same problems. Notice! For this week only duplicates will be accepted. Please note that in future weeks there will be enough questions for everyone to pick their own questions and duplicates will not be accepted. You need to:*show work to find solution (you can use an embedded image or the fx button on the Rich Text Editor if appropriate)*explain in the text how you approached and worked through the problemIdeally, you will choose problems that you had a hard time solving until something clicked (which you would then explain--what you figured out that you did wrong, etc.). Either way, you should lead a discussion about the problem. This will help everyone go through the thought process of these problems, see different ways that students set them up, compare approaches, maybe learn new strategies and hints, recognize mistakes, etc. If you cannot solve the problem at first, no worries, your classmates and myself will give you help you along and you can edit your problem until it is due. If you are having trouble, show your work and explain where you are getting stuck. Remember, you are not getting graded on whether you solve the problems correctly, but rather the attempt you make and the discussion you have with us related to it. So it will likely be more beneficial to you to select challenging problems with which you need help as opposed to easy ones that you can already solve.Initial Post Due: Thursday of Week 3, by 11:55pm ETResponses Due: Sunday of Week 3, by 11:55pm ET

Graded Assignment Lab Report Question:  How do different metals act in solution and react with other compounds? Hypothesis:  Use your knowledge of the periodic table to write a hypothesis that describes how a transition metal might behave differently from a nontransition metal. Write your hypothesis as an if-then statement. (2 points) Procedure 1. Place 10 drops of KNO3 in wells 1A, 1B, and 1C of microplate 1, as shown in the table below. Place 10 drops of Ca(NO3)2  in wells 2A, 2B, and 2C. 2. Continue this pattern of placing 10 drops in three wells for each of the compounds listed in the table. 3. Add 10 drops of NH4OH to each well in row A of each microplate. In each case, mix thoroughly with stirring rod. 4. Add 10 drops of HCl to each well in row B. In each case, mix thoroughly with a stirring rod. 5 .Continue this pattern of placing 10 drops in the wells as shown in the table. Do not add anything to the control wells. 6. Observe the controls. Record your descriptions of the controls. 7.  Observe rows A and B on each microplate with a hand lens. Record any variations from the control, if no reaction record NR Table 1  Observations After Mixing the Reactants for Microplate 1 1 Metal is K KNO3  10 drops 2 Metal is Ca Ca(NO3)2  10 drops 3 Metal is V NH4VO3  10 drops 4 Metal is Mn MnSO4  10 drops A  (NH4OH) 10 drops B  (HCl) 10 drops C  (Control) KNO3 Ca(NO3)2 NH4VO3 MnSO4 5 points Table 2 Observations After Mixing the Reactants for Microplate 2 1 Metal is Fe Fe(NO3)3 2 Metal is Co Co(NO3)2 3 Metal is Cu Cu(NO3)2 4 Metal is Zn Zn(NO3)2 A  (NH4OH) 10 drops B  (HCl) 10 drops C (Control) Fe(NO3)3 Co(NO3)2 Cu(NO3)2 Zn(NO3)2 5 points Answer the questions below. When you have finished, submit this assignment to your teacher by the due date for full credit. (2 points) Score 1.  Which combinations of substances resulted in a chemical change? Answer: (2 points) Score 2.  For each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. Answer:  Transition:  Nontransition: (2 points) Score 3.  Were there any metallic compounds that did not react with either the acid or the base? Write the type of metal, based on your examination of the periodic table. Answer:  Transition: Nontransition: (2 points) Score 4.  Make a general statement about the reactivity of the metals in this experiment. Answer: (Hint…which were more reactive, transition or nontransition) Your Score ___ of 20