At which time, 1:30 or 1:38, do you think opposite rays form?

What is the product? a-3/15a × 5/a-3

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of

The given diagram shows the parts of a right triangle with an altitude to the hypotenuse. using the two given  measures, find the other four.