1) Right answer:
en la segunda hora
In second period means en la segunda hora. Recall that period is a length or portion of time. So hora here translates into period. The word la is the definite article (translating as the) that matches the feminine singular form. We choose the feminine singular form of the definite article because segunda hora also matches the feminine singular form. Recall that in Spanish, definite article must match the noun they describe in both gender and number.
2) Right answer:
13:30
The 24 hour time comes from 00:00 to 23:59. So, the main times are the following:
00:00 → 12:00 a.m
01:00 → 01:00 a.m
02:00 → 02:00 a.m
03:00 → 03:00 a.m
04:00 → 04:00 a.m
05:00 → 05:00 a.m
06:00 → 06:00 a.m
07:00 → 07:00 a.m
08:00 → 08:00 a.m
09:00 → 09:00 a.m
10:00 → 10:00 a.m
11:00 → 11:00 a.m
12:00 → 12:00 p.m
13:00 → 01:00 p.m
14:00 → 02:00 p.m
15:00 → 03:00 p.m
16:00 → 04:00 p.m
17:00 → 05:00 p.m
16:00 → 04:00 p.m
17:00 → 05:00 p.m
18:00 → 06:00 p.m
19:00 → 07:00 p.m
20:00 → 08:00 p.m
21:00 → 09:00 p.m
22:00 → 10:00 p.m
23:00 → 11:00 p.m
Therefore, 1:30 corresponds to 13:30
3) Right answer:
the science class is boring
La clase de viencia naturales es aburrida means the science class is boring. The word boring describes things or situations that make you feel bored while bored describes how you feel. So you don't like science class because it is boring. Both boring and bored translates into the same Spanish adjective aburrido/a
4) Right answer:
they walk
Many people in Puerto Rico can't afford the money to go on buses, bikes, or cars. Therefore, students often go to schools they are in through walking. Moreover, walking around towns in Puerto Rico is safe and you can find a lot of students doing that.