When is subtraction always the first operation done in an expression? Never
When it follows addition in an expression.
When it is the first operation in an expression, from left to right.
When it is in parentheses in an expression.

Step-by-step explanation:

The order of operations tells us the correct steps for solving a math problem. Subtraction is the last step, so if none of the 5 steps before it are in the equation, then that is when you will do subtraction first.

When it is the first operation in an expression, from left to right.

the answer is 0.071

good luck! : d

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.