Respuesta :
Answer:
180/3 60 second
Step-by-step explanation:
21/7 = 3 feet per second
60 secconds
Explanation;
21 feet /7 secconds =3 secconds per foot.
180/3=60
Explanation;
21 feet /7 secconds =3 secconds per foot.
180/3=60