Please help expected value with empirical probabilities

What two criteria are needed for triangles to be similar

You are on a cycling trip around europe with friends. you check the weather forecast for the first week. these are the temperatures for the week. sun mon tues wed thurs fri sat 16°c 20°c 24°c 28°c 28°c 23°c 15°c what is the mean temperature forecast for the week?

Find the measure of angle y. round your answer to the nearest hundredth. ( type the numerical answer only) a right triangle is shown with one leg measuring 5 and another leg measuring 14. an angle across from the leg measuring 5 is marked y degrees. numerical answers expected!