Scientists are measuring the thickness of ice on a large lake. When they first measure the ice, it is 3.1 inches thick. Three weeks later the ice was measured to be 5.5 inches thick.

Step-by-step explanation:

What is the question?

Amount of change = 5.5-3.1 = 2.4 inches

Percentage change = 2.4/3.1 ≈ 77.4% increase

option a, c,d are correct.

step-by-step explanation:

from the given figure, it is given that z is equidistant from the sides of the triangle rst, then from triangle tzb and triangle szb, we have

tz=sz(given)

bz=zb(common)

therefore, by rhs rule,δtzb ≅δszb

by cpctc, sz≅tz

also, from δctz and δasz,

tz=sz(given)

∠tcz=∠saz(90°)

by rhs rule, δctz ≅ δasz, therefore by cpctc, ∠ctz≅∠asz

also,from δasz and δzsb,

zs=sz(common)

∠zbs=∠saz=90°

by rhs rule, δasz ≅δzsb, therefore, by cpctc, ∠asz≅∠zsb

hence, option a, c,d are correct.