Assume each member can be chosen for one position only, Then the choice for President is 30 choose 1 = 30. The number of ways can a 5-member committee be formed will be C. 142,506. This is caused by permutations and combinations.
How to calculate the value?
From the information, the Science Club has 30 members and needs to elect officers. They will need a President, Vice President, Secretary, treasurer, and historian.