How many solutions does 400=x times x have

In an experiment you are to flip a two sided coin 100 times and record 55 heads up and 45 tails up determine the theoretical and experimental probability of getting a heads up in the experiment.

Find the exact value of each of the following. in each case, show your work and explain the steps you take to find the value. (a) sin 17π/6 (b) tan 13π/4 (c) sec 11π/3

What is the perimeter of a rectangular building that is 80 feet wide and 140 feet deep?