Hello,
N is closed for an opération(µ) means that
a,b ∈ N : a µ b ∈N (i suppose so)
Answer (1) ex 2/3 ∉ N
Answer (4) ex 2-3 ∉ N
∀ a,b ∈ N: a+b ∈N is true ; not a answer.
∀ a,b ∈ N: a*b ∈N is true ; not a answer.
Cant answer this without giving an equation
Answer:
25 meters
Step-by-step explanation:
30 km/hr = (30 km/1 hr)*(1000 m/1 km)*(1 hr/60 min)*(1 min/60 sec)
30 km/hr = (30*1000*1*1)/(1*1*60*60) meters per second
30 km/hr = 8.3333333333 m/s (approximate)
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The speed or rate is r = 8.3333333333 meters per second approximately, and the time is t = 3 seconds, so,
distance = rate*time
d = r*t
d = 8.3333333333 * 3
d = 24.9999999999
Due to rounding error, the true answer should be d = 25. We can see this if we opted to use the fraction from of 8.3333... instead of the decimal representation which isn't a perfect exact measurement.
I believe it would be x+5^2
