Lúcia is using energy at a rate of 420 kilocalories(kcal) per hour (start text, h, end text, ) ice skating. At what rate is Lúcia using energy in calories per minute left parenthesis, \frac cal/- end fraction, right parenthesis?

7000 calories /minutes

Step-by-step explanation:

420 kilocalories / hour

To convert  kilocalories / hour to calories / minutes

kilo means 1000 and 60 minutes is equivalent to 1 hour

therefore

= (420*1000 calories) / 60minutes

= (420000 / 60) calories/minutes

= 7000 calories /minutes

answer: the angel abc is 30°,and the abc is a triangle where the angel bac is 90°

so ac is the half of 24=12ft,and from the pythagorean theorem we find ba

ba=√bc^2-ac^2=√576-144=√432=12√3ft

so bac is 12+12√3=12(1+√3)ft