A manufacturer must test that his bolts are 2.00 cm long when they come off the assembly line. He must recalibrate his machines if the bolts are tc long or too short. After sampling 169 randomly selected bolts off the assembly line, he calculates the sample mean to be 2.05 cm . He knows that th population standard deviation is 0.29 cm . Assuming a level of significance of 0.01 , is there sufficient evidence to show that the manufacturer needs to recalibrate the machines? Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below. Answer 2 Points Keyboard Shortcuts

15. Suppose data collected for heights (in cms) of 390 cows were tabulated in a frequency distribution and the following results were obtained. fi: \( 6,25,48,72,116,60,38,22,3 \) CMI \( =112, \mathrm{CM} 2=117 \) where CMi ith class mark Determine: a) Class interval size (class width), Class limits, Class boundaries and class marks b) The less than cumulative frequency distribution c) The class intervals having the highest frequency d) Above which height do we find \( 50 \% \) of the cows? c) Below which height do we get \( 25 \% \) of the cows? Draw a) histogram b) a frequency polygon c) C. a less than ogive for the above data

61. Mode is the value with maximum frequency in the data. 62. Fermions are classified as Leptons and Baryons. 63. A muxture in which the composition is not uniform throughout is called heterogeneous mixture 64. The arithmetic mean of first ' \( n \) ' natural numbers is \( \frac{n}{2} \) ' 65. Symmetric encryption is slower than asymmetric encryption. 66. \( |7|=0 \)

Which sampling Which sampling method is better? Why? Which sampling method you might use in Assignment \# 2 (Marketing Dashboard)? Why?

What is a scatter plot?

The mean weight of 150 students in a certain class is 60 Kg . The mean weight of boys in the class is 70 Kg and that of the girls is 55 Kg 。 Find the number of boys and the number of girls in the class.