The research of astronomy during the time period of 1970 - 1990 is given below:
<u>Date</u> <u>Event</u>
1. 15 June 1974 Black Brant VC sounding rocket from White Sands.
2. 14 May 1973 Launch of Skylab, the USA's first space station
3. 26 July 1971 Launch of Apollo 15
<h3>What is Astronomy?</h3>
This refers to the branch of science that deals with celestial bodies and their relation to each other.
Hence, from information about astronomy, between the time period 1970 - 1990 as it was on the 26th of December, 1974 that the Soviet space station Salyut-4 was launched.
The event I think had the greatest impact in astronomical history during this time period was the launch of Apollo 16.
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1. Magnesium atoms also have a slightly smaller radius than sodium atoms, and so the delocalised electrons are closer to the nuclei.
2. Sodium has higher melting point than potassium because of stronger metallic bonding .
3. Potassium are very soft metal can be very easily cut with a knife
4. Increase of resistance in metals. Therefore the mobility of electrons decreases and causes decrease in conductivity.
5.To increase strength, increase corrosion resistance, or reduce costs.
6. All metals have low ionization energies and are relatively electropositive, and so they lose electrons fairly easily.
7. All the group 1 metals are reactive, but they get more reactive as you go down the group, so potassium is more reactive than sodium.
Vertical-horizon.
If neither of them are it then it’s columns
Scale and measuring tape.
To determine the mass and volume, you can find the density. The block will float if its density is less than that of water.
Answer:
A double displacement reaction or double replacement reaction.
Explanation: