please i want help with differential engineering math assignment

/in /by

please write the answers with details and clear hand writing do not copy the work from chegg or anything else , please do:

Sec 1.1: Problems #1, 19;

Sec 1.2: Problems #2, 13, 28 (Direct Integration)

Sec 1.4: Problems #2, 11, 26, 37 (Separation of Variables; Models)

Sec 1.5: Problem #3, 8, 15, 37 (Integrating Factor Method)