Answer:
The corrected sentence is: "The first man in space, Yuri Gagarin, made a single orbit of the planet Earth and reached an altitude of 188 miles."
Step-by-step explanation:
Misspelled word: Plant. Should be planet.
Missing commas: Before and after the name of the cosmonaut.
Capitalizations errors: The first and last name of the cosmonaut. Earth.
Verb error: It should be "reached" instead of "reaches" because the sentence is in past tense.