Answer:
Community trial type of study.
Explanation:
• Since 1945, fluoride was added to Newburgh's water supply.
• Water supply in Kingston was not fluoridated.
• The two communities were experiencing similar tooth decay condition.
• After 10 years, children from Newburgh experienced less tooth decay compared with their counterparts at Kingston, with no side effect on their health.
It was false because it tells u in the story
Answer:
Chipping; cutting; drilling; grinding
Explanation:
Activities such as abrasive blasting with sand; sawing brick or concrete; sanding or drilling into concrete walls; grinding mortar; manufacturing brick, concrete blocks, stone countertops, or ceramic products; and cutting or crushing stone result in worker exposures to respirable crystalline silica dust.
Answer:
The additive drag at flight condition will be found by the following equation
Area = A1 = 6m2
Da = Additive drag
Cda = Additive drag coefficient
P = prassure at altitude of 12Km
Po = Prassure at sea level
\gamma = Ratio of specific heat capacity
The formula of additive drag is given below
D = Cda q A
q = Dynamic prassure , A = cross sectional area
q =( \gamma/ 2) P0 M02
D = Cda ( \gamma/2) po Mo2 A
Cda=0.32
\gamma=1.4
M=0.8
p0= 101325pa
D = 0.32 (1.4/2)(101325pa)(0.6)2 6
D = 49025N
Explanation:
The additive drag at the flight conditions will be D= 49025N
