Which statement best describes the function h(t) = 210 – 15t?

Let the closed interval [a , b] be the domain of function f. the domain of f(x - 3) is given by (a) the open interval (a , b) (b) the closed interval [a , b] (c) the closed interval [a - 3 , b - 3] (d) the closed interval [a + 3 , b + 3]

The ratio of the measures of the three angles in a triangle is 2: 9: 4. find the measures of the angels

Having a hard time understanding this question (see attachment).