The range of a Tesla electric vehicle on a single charge will depend on a number of factors, 

including the specific model of the vehicle, the conditions in which it is being driven, and the driving habits of the driver. 

In general, driving at higher speeds will result in a shorter range, as the vehicle will consume more energy to maintain a higher speed. 

As an example, the Tesla Model 3, which is one of the company's most popular models, 

has a range of up to 358 miles on a single charge under optimal conditions, according to Tesla's website. 

However, this range will be lower if the vehicle is driven at high speeds or in challenging conditions, such as in hilly terrain or in extreme cold or heat.

At a constant speed of 70 mph, the range of the Model 3 would likely be significantly lower than its maximum range. 

According to Tesla's website, the Model 3 has a range of up to 220 miles at a constant speed of 70 mph. 

This is based on the EPA's highway driving cycle, which includes factors such as wind resistance, tire rolling resistance, and air conditioning usage.

It's worth noting that these estimates are based on laboratory testing and may not accurately reflect real-world driving conditions. 

The actual range of a Tesla electric vehicle on a single charge will depend on a variety of factors and 

There are a few other factors that can affect the range of a Tesla electric vehicle on a single charge: 

1. Climate: Extreme cold or heat can affect the range of an electric vehicle, as the battery will perform differently in different temperatures. 

In cold weather, the battery may not deliver as much power as it would in warmer conditions, which can result in a shorter range.