Answer:
The given expression
on multiplying is 
Step-by-step explanation:
Consider the given two expressions
and 
We have multiply both expressions,

To multiply two terms first multiply constant numbers that is 6 × 2 = 12
For x , y and z apply property of exponent,

Then power of x together will be,

Similarly for y powers,

Since first term do not have any expression for z so it will remain same.
Thus, the given expression on multiplying become,
is 
Answer:
(a) see attachment
(b) E(x) = 226/105
Step-by-step explanation: see attachment
If you mean unit rate you find it by dividing the top number by the bottom number to fin the singular number or unit rate.
98 Cm should be the answer
(x2-x1)/(y2-y1)
(1+2)/(1-13)
3/-12
the slope of the graph is -1/4