Definite article for agenda escolar

Achemist mixes 4 liters of one acid solution with 10 liters of a 40% solution, resulting in a 30% acid solution. what is the value of x, the acid concentration of the first solution

Fill in the blank with the spanish word that best completes the following sentence. allí está mi casa. vivo muy aquí. lejos a la derecha cerca calle

Based on the audio, why do you think the friends get together to have  chocolate con churros? the friends get together to have  churros con chocolate  to   try this snack  socialize  see the puerta del sol  see the bear statue