I think is is A. welding torches
Answer:- Mass of the titanium alloy is 7.01 g, choice C is correct.
Solution:- The heat of fusion is given as 422.5 joules per gram and it also says that 2960 joules of heat is required to melt the metal completely.
The suggested equation is, 
where Q is the heat energy, m is the mass and Hf is the heat of fusion.
Since, we are asked to calculate the mass, the equation could be written as:
Let's plug in the values in it:
m = 7.01 g
So, the mass of the titanium alloy is 7.01 g, choice C is correct.
Answer is D
Explanation: A gamma ray primarily consists of pure energy and no mass.
Phenolphthalein turn pink in basic solutions.it turn colourless in acid solution.
Hence options(1)is correct
Answer:
Limestone is easily eroded from above and below.
Explanation:
The Florida bedrock is largely made of limestone. Because limestone is a rock that is easily eroded, the landscape of a great part of Florida is classified as karstic.
Karstic landscapes are dotted by sinkholes, underground rivers, caves, and springs. The more acidic the groundwater or rainwater, the faster and more easily the limestone will succumb to erosion.
In this way, underground rivers, streams, runoff, rain, and underground water pooled in caves have all carved out gaps and caverns in the weak limestone bedrock.
