How do you do this ? i need with the question

If the alternate hypothesis of an experiment is “the true mean height of the giraffes is more than 15 feet” what is the null hypothesis?

Breana is selling tickets to a choral performance. on the first day of ticket sales , she sold 3 senior citizen tickets and 1 child ticket for a total of $38. breana took in $52 on the second day by selling 3 senior citizen tickets and 2 child tickets. what is the price of a senior citizen ticket?

Situation: find the age of the skull to the nearest year, enter the correct answer. a hiker in africa discovers a skull that contains 32% of its original amount of c- 14. done n = noekt 00000 no = inital amount of c-14 (at time t = 0) n = amount of c-14 at time t k = 0.0001 t = time, in years