Solve the Problem $\begin{array}{r}x+4 y \leq 100 \\10 x+3 y \leq 70 \\.75 x+3 y \leq 45\end{array}$

Solve the problem.
-A steel company produces two types of machine dies, part A and part B and is bound by the following constraints:
· Part A requires 1 hour of casting time and 10 hours of firing time.
· Part B requires 4 hours of casting time and 3 hours of firing time.
· The maximum number of hours per week available for casting and firing are 100 and 70, respectively.
· The cost to the company is $0.75 per part A and $3.00 per part B. Total weekly costs cannot exceed
$45.00.
Let x = the number of part A produced in a week and y = the number of part B produced in a week. Write
A system of three inequalities that describes these constraints.

A)
$\begin{array}{r}x+4 y \leq 100 \\10 x+3 y \leq 70 \\.75 x+3 y \leq 45\end{array}$
B)
$\begin{array}{r}x+10 y \leq 100 \\4 x+3 y \leq 70 \\0.75 x+3 y \leq 45\end{array}$
C)
$\begin{array}{r}x+10 y \geq 100 \\4 x+3 y \geq 70 \\0.75 x+3 y \leq 45\end{array}$
D)
$\begin{array}{r}x+4 y \leq 100 \\10 x+3 y \leq 70 \\3 x+0.75 y \leq 45\end{array}$