1. Which of the following is the fastest speed? Show your working.

(a) 60 km/h
(b) 15 m/s
(c) 1.1 km/min

60 km/h = 60*1000m/3600s = 16.67 m/s, which is larger than(b)

1.1 km/min= 1100 m/60 s = 18.33 m/s,
which is faster than (a) and (b)

So the answer is (c)

To determine which speed is the fastest, we need to compare the speeds given in different units and convert them to a common unit. In this case, we will convert all speeds to meters per second (m/s) since it is the standard scientific unit for speed.

(a) 60 km/h:
To convert kilometers per hour (km/h) to meters per second (m/s), we need to divide by 3.6, since 1 km/h is equal to 1000 meters divided by 3600 seconds.
60 km/h = (60,000 meters / 3600 seconds) = 16.67 m/s

(b) 15 m/s: This speed is already given in meters per second.

(c) 1.1 km/min:
To convert kilometers per minute (km/min) to meters per second (m/s), we need to divide by 60, since there are 60 seconds in a minute.
1.1 km/min = (1,100 meters / 60 seconds) = 18.33 m/s

Comparing the converted speeds:
(a) 16.67 m/s
(b) 15 m/s
(c) 18.33 m/s

From the given speeds, the fastest speed is 18.33 m/s, which corresponds to option (c) - 1.1 km/min.