Given s = 2.4 b = -7.2 t = 4.8 n = -9.6, evaluate this mathematical expression (s - b)(n + t). These are the answer options:
23.04

-23.04

46.08

-46.08

Fourth Choice. -46.08

Concept:

Here, we need to understand the idea of evaluation.  

When encountering questions that gave you an expression with variables, then stated: "If x = a, y = b, z = c" (a, b, c are all constants), this means you should substitute the value given for each variable back to the expression.

Solve:

Given information

s = 2.4

b=-7.2

t=4.8

n=-9.6

Given expression

(s - b) (n + t)

Substitute values into the expression

= (2.4 - (-7.2)) (-9.6 + 4.8)

Simplify values in the parentheses

= (2.4 + 7.2) (-4.8)

=(9.6) (-4.8)

Simplify by multiplication

=

Hope this helps!! :)

Please let me know if you have any questions

2.2°  

step-by-step explanation:

let θ = the angle of elevation.

tanθ =77/2020

tanθ = 0.038 12

      θ = tan⁻¹0.038 12

      θ = 2.2°