The lockers at smith high school are numbered 1-1000. seth starts at the beginning and opens the even numbered lockers. tacoda then starts at the beginning and opens all numbers that are multiples of 2. lastly, brady starts at the beginning and opens all numbers that are multiples of 5. which is the first locker that brady is supposed to open that is already open?
a) 10
b) 15
c) 30
d) 60

i think it is 70

step-by-step explanation:

1. 180°. the sum of the interior angles of a triangle is 180°, for the equilateral triangle that it has three equals side is 60°+60°+60°=180°.

2. 60°. each interior angle of a equilateral triangle is 60°

3. 120°. the measure of ∠m is 120°, the sum of the angles ∠m and ∠n is equal to 180°. so, in order to find the measure of ∠m, we have ∠m+∠n=180° > ∠m=180°-∠n > ∠m=180°-60°=120°.

4. 360°. the sum of the exterior angles of an equilateral triangle is ∠m+∠r+∠x=120°+120°+120°=360°. the exterior angles of any triangle always add 360°.