Answer:
A. T > 2.539
Step-by-step explanation:
We have a hypothesis test of the mean, with unknown population standard deviation.
The hypothesis are:

From the hypothesis we can see that the test is right-tailed, so the critical value of t should be a positive value.
The degrees of freedom can be calculated as:

The significance level is 0.01, so the critical value tc should be the one that satisfies:

Looking up in a t-table, for 19 degrees of freedom, this critical value is tc=2.539.
The first 5 Multiples of 7<span> are 35, 70, 105, 140, 175
</span>The first 5<span> Multiples of </span>20<span> are: </span>20<span>, 40, 60, 80, 100
</span>
Let C be the center of the circle. The measure of arc VSU is
, so the measure of the minor arc VU is
. The central angle VCU also has measure
.
Triangle CUV is isosceles, so the angles CVU and CUV are congruent. The interior angles of any triangle are supplementary (they add to 180 degrees) so


UT is tangent to the circle, so CU is perpendicular to UT. Angles CUV and VUT are complementary, so



So finally,

degrees.
Substitute 2 into x in the equation so f(x)= 5x2 -12 = -2 so it’s C = -2