Answer:
y = 43.55 + 2.15t
Explanation:
We were told that in 1983, the per capita consumption was 37.1 pounds, and in 1989 it was 50 pounds.
If we assume t = 0 corresponds to year 1980. Then, for 1983 it will be t = 3 and for 1989,it will be t = 9.
Thus, expressing the information as ordered pairs, we have; (3,37. 1) and (9,50).
Let us now find slope of the linear function:
m1 = (y2 - y1)/(t2 - t1)
m1 = (50 - 37.1)/(9 - 3)
m1 = 2.15
So, we can find the linear equation as;
y - 37.1 = 2.15(t - 3)
y = 37.1 + 2.15t - 6.45
y = 43.55 + 2.15t
Answer:
.
Explanation:
The efficiency of a machine is the percentage of energy input that was turned into useful energy.
The power rating of this lamp is 
(same as 
,) meaning that 
of energy is supplied to this lamp every second.
The question states that 
out of that of energy input would be turned into heat, which is not useful energy output in this scenario. Assuming that all other forms of energy loss is negligible. The rest of the 
of energy supplied to this lamp would be turned into useful energy output.
Thus, every second, this lamp would receive of energy input and would outputs 
of useful work. The efficiency of this lamp would be:
.
