- ID
- 2003938
- Banca
- Aeronáutica
- Órgão
- EEAR
- Ano
- 2012
- Provas
- Disciplina
- Inglês
- Assuntos
Since astronaut Yuri Gagarin became the first man to travel in space in 1961, scientists _________ what effects space travel has on the human body.
(Adapted from Active Skills)
Fill in the blank with the correct verb tense.