Fernando has 22 coins consisting of nickels and dimes in his pocket, The total value of the coins is $1.70
which system of equations can be used to determine the number of
nickels, n, and the number of dimes, d, in his pocket? ANSWER CHOICES IS IN THE PICTURE

The anwser cause i do not understand just plez

Line wx is parallel to line yz. if m

A. find the power of the test, when the null hypothesis assumes a population mean of mu = 450, with a population standard deviation of 156, the sample size is 5 and the true mean is 638.47 with confidence intervals of 95 b. find the power of the test, when the null hypothesis assumes a population mean of mu = 644, with a population standard deviation of 174, the sample size is 3 and the true mean is 744.04 with confidence intervals of 95% c. find the power of the test, when the null hypothesis assumes a population mean of mu = 510, with a population standard deviation of 126, the sample size is 10 and the true mean is 529.44 with confidence intervals of 95