Difference between ring, integral domain and field

Which one of the following is a trick used in spanish to identify the right hand? touch the tips of your index fingers with the tips of your thumbs. the hand that forms a lowercase b is your mano derecha. touch the tips of your index fingers with the tips of your thumbs. the hand that forms a lowercase d is your mano izquierda. touch the tips of your index fingers with the tips of your thumbs. the hand that forms a lowercase d is your mano derecha.

Ojalá que uds. a clase mañana. a. saben b. vienen c. vengan d. sepan

Me gusta autobus a.andar b.empezar c.tomar d.tener