C. No, this is not a valid inference because she asked only 35 families
Answer:
The person invested $3500 at 7% and $2500 at 5%
Step-by-step explanation:
We can say that
because the investment is equal both in one as in another, where x is the income from the investment.
Solving the equation we have:

Then to get the incomes:
At 7%: 
And at 5%: 
Finally we can demonstrate the answer because the income at 7% + income at 5% are 3500+2500=$6000
Answer:
The area of a trapezium is computed with the following formula: Area = 1 2 × Sum of parallel sides × Distance between them.
Step-by-step explanation:
Hope it help! :)