What do you understand by oscillating universe theory?

Can someone me with these questions ?

Question 11 (fill-in-the-blank worth 1 points) change this verb from the present tense to the preterite tense. tú estudias answer for blank 1: question 12 (fill-in-the-blank worth 1 points) change this verb from the present tense to the preterite tense. raúl estudia answer for blank 1: question 13 (fill-in-the-blank worth 1 points) change this verb from the present tense to the preterite tense. nosotros pagamos answer for blank 1: question 14 (fill-in-the-blank worth 1 points) fill the blank with the preterite tense of the verb in parentheses. usted a la tienda por teléfono. (llamar) answer for blank 1: question 15 (fill-in-the-blank worth 1 points) fill the blank with the preterite tense of the verb in parentheses. lolita pablo en la fiesta anoche. (hablar) answer for blank 1:

Decide whether the sentence is grammatically correct or incorrect as written.¿preguntas una chaqueta nueva para la navidad?