Can some one help me with these to questions if you do I will give you brain list

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

(x-5)1/2+5=2 what is a possible solution?

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.