5.3.4 Practice: Modeling: Finding Parallelograms Please help (I am giving 100 points and will make brainiest)

I have attached the questions on a PDF down below

Ricardo ran the 400 meter race 3 times his fastest time was 54.3 seconds his slowest time was 56.1 seconds if his average time was 55.0 seconds what was his time for the third race

5.(04.07) two different plants grow each year at different rates, which are represented by the functions f(x) = 4* and g(x) = 5x + 2. what is the first year the f(x) height is greater than the g(x) height? year 3 year 0 year 2 year 1

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?