Arduino pro mini v5 on-board MIC5205 150mA LDO Regulator

I am currently working on a hand prosthetic and am developing a wearable wristband to read emg signals. The wristband contains the following:

1) Arduino Pro mini 5V ( Typical supply voltage: +5.0 V, Typical supply current: 10-25 mA)

2) Transmitter Module ( Typical supply voltage: +5.0 V, Typical supply current: 03-10 mA)

3) Myoware muscle sensor ( Typical supply voltage: +5.0 V, Typical supply current: 09-14 mA)

I am currently looking for a battery to power these components. The battery needs to be as small and as light as possible. It also needs to be rechargeable. There is no minimum operation time due to the project being a prototype, however, the longer the duration the better. I am currently looking at the s 200mAh 2S 7.4v 20C LiPo Battery ( http://www.overlander.co.uk/batteries/lipo-batteries/eflite-umx-beast-type-lipo-battery.html )

QUESTION 1) Will this battery work fine with the components mentioned above?

QUESTION 2) will it work for roughly hours as I calculated?

0.2 Ah /(25 mA+10 mA+14 mA)= 4 h

QUESTION 3) looking at the Arduino on-board voltage regulator (http://www.micrel.com/_PDF/mic5205.pdf) I calculate that there will be 0.379 W power dissipation is the value correct?

Pd=(7.4 V-5 V)*150 mA + 7.4 V *2.5 mA = 0.379 W

QUESTION 4) I also calculate that the voltage regulator temperature rise will be 83.83 C is the vale correct and is it normal or do I need a heat sink?

TempRise= 0.379 W*220 = 83.83 C

Thank you for your time :)

Wasferd: I am currently working on a hand prosthetic and am developing a wearable wristband to read emg signals. The wristband contains the following:

1) Arduino Pro mini 5V ( Typical supply voltage: +5.0 V, Typical supply current: 10-25 mA)

2) Transmitter Module ( Typical supply voltage: +5.0 V, Typical supply current: 03-10 mA)

3) Myoware muscle sensor ( Typical supply voltage: +5.0 V, Typical supply current: 09-14 mA)

I am currently looking for a battery to power these components. The battery needs to be as small and as light as possible. It also needs to be rechargeable. There is no minimum operation time due to the project being a prototype, however, the longer the duration the better. I am currently looking at the s 200mAh 2S 7.4v 20C LiPo Battery ( http://www.overlander.co.uk/batteries/lipo-batteries/eflite-umx-beast-type-lipo-battery.html )

QUESTION 1) Will this battery work fine with the components mentioned above?

QUESTION 2) will it work for roughly hours as I calculated?

0.2 Ah /(25 mA+10 mA+14 mA)= 4 h

No. A battery's output is not linear. It decreases as it is discharged. For safety, I would halve that figure.