The answers are:
Dan aprendiĂł a bucear
Because “aprendiste” means (single) you learned
”aprendimos” means “we learned”
“Aprendieron” means “they learned”
¿A qué hora saliste tú?
“SalĂ” means “I left”
“Salieron” means “they left
And ”salisteis” means (plural) you left.