Need help with growth of the pattern, number of tiles in figure 0 and pattern equation

Which of the fallowing best completes the sequence 5,10,15, a) 30 b) 22 c)25 d)35

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e.g. 98.76543).

Which angle of rotation is an angle of rotational symmetry for all figures?