What is the last digit of the following expression: 1·2·3·...·2019−(7*7*7*7*7*7*7)−1·3· 5·...·2017?

Please help I need it now!!

Yoku is putting on sunscreen. he uses 2\text{ ml}2 ml to cover 50\text{ cm}^250 cm 2 of his skin. he wants to know how many milliliters of sunscreen (c)(c) he needs to cover 325\text{ cm}^2325 cm 2 of his skin. how many milliliters of sunscreen does yoku need to cover 325 \text{ cm}^2325 cm 2 of his skin?

If x is 6, then 7x= a. 13 b. 42 c. 42x d. 76

Aswimming pool measures 22ft by 12ft and is 4ft deep. if the pool is being filled at 2.5 cubic ft per minute, how long will it take to fill the pool?